Can I drive 3 boards' Rx pins from 1 board's Tx pin?

I have a Pro Mini which I want to send the same data to 3 other Pro Minis. They will only receive and the 1 sender will only send. I know that TTL can "fanout" from one output to up to 10 TTL inputs. So can I have 1 Pro Mini use its Tx pin to drive the other three boards' Rx pins? I want to drive all 3 at the same time and not multiplex them. Thanks for listening.

Though I am not pro in this case of yours, but I tried it once, and it works, only if you block serial communication for none but one Pro Mini. You can try disabling the serial interface, then try it, so that not all Pro Mini(s) try to "talk" at the same time. Else avrdude returns 'device not responding' error

Yes, but it may be necessary to disconnect the network for programming and such. There may also be complications driving the network if the boards are separated by a significant distance.

Three of the Pro Minis will only receive and a fourth Pro Mini will only send. There won't be any kind of network, the project will just have the 4 boards in close proximity sharing a single power supply. If I get this project working, they won't need a connection to be programmed or communicate with other devices. Hopefully this will be a simple project to cut my teeth on and won't have complications to deal with (the operative word being 'hopefully").